I don't think they've been to bed. Most of us have items in our clo closet that we tefr wear. There's a new way to cash in. It's an app that opens your closet to anyone. Rebecca Jarvis is here with this. You want to think of this app as a cross between Ebay and Pinterest. What do fashion mogul Rachel Zoe and Hollywood hot too Ashton Kutcher have in xon? Well, they're all investors in a little something called posh mark. It's an interesting virtual closet. Women can swap or buy each other's clothes. Reporter: You can sell or buy anything from dresses to jeans, tops, shoes, bags, accessoriaccessories. Take a vote, describe it, post it. Voila. It got born out of our own closet. My wife has bags and bags of fashion lying there unopened. Reporter: There are over 300,000 active closets. These are the clothes I'm selling. Reporter: And for 21-year-old college student Hannah, how did you get started on poshmark? Jt I got a sweater that looked terrible on me. It sold within 20 minutes. It's different. It's got an instagram feel. User to user. Reporter: She now uses poshmark to run her own business selling jewelry and has over 2 million followers. Show me how it's done. Click the sell button. Take a quick picture. Write a little title. So, I'm going to write, peplum top. How many things have you listed? 6,000 items. Reporter: How much money have you made? Over $80,000. Reporter: That must go a long way toward paying for college? It is definitely helping pay my expenses. Reporter: If you find the top, you know where you saw it first. And here's how the money part does work. You choose the price. Once you sell the item, poshmark takes a 20% xigs. They always cover the shipping costs. Also the other elements is security. They don't remit payment until you say this item works for me. So you have to say you like it in order for them to pay. It sounds easy and reasonable. That's how it appears. This falls along, as always, on ginger lines. We can go shopping in our own closets all the time. But the guys? No? Everything we buy, we wear. Probably the same day. It stuns me. Thanks, rebeck la. We turn to our mourn exclusive with Miley Cyrus.

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